President Donald Trump plans to send the National Guard to the Mexican border to bolster security until his promised border wall is built, the White House said Tuesday, according to The Hill.

Trump earlier in the day told reporters he planned to deploy the U.S. military to guard the border and he would abandon NAFTA without assurances of help on securing the boundary.

"We are going to do some things, I've been talking to Gen. Mattis, we're going to be doing things militarily until we can have a wall and proper security," Trump said Tuesday during a meeting with the leaders of Estonia, Latvia, and Lithuania. "We're going to be guarding our border with the military."

The White House did not specify when the plan would be implemented. The National Guard has been used in recent years for intelligence and surveillance on the border, but not for direct law enforcement.

Under Republican President George W. Bush, the National Guard between 2006 and 2008 provided border-related intelligence analysis, but had no direct law enforcement role.

In 2010, President Barack Obama sent National Guard troops to the U.S.-Mexican border to provide intelligence, surveillance, and reconnaissance support to U.S. Border Patrol agents.

Trump campaigned on a promise to build a wall, and has been pushing for one since he took office. The president wanted as much as $25 billion to fund it, but the omnibus spending bill approved last week only authorized for $1.6 billion for fencing, surveillance technology, and other measures.